void left_rotate(SBTreeNode **node)
{
	SBTreeNode *temp = (*node)->rchild;
	(*node)->rchild = temp->lchild;
	temp->lchild = *node;
	temp->size = getSize(*node);
	(*node)->size = getSize((*node)->lchild) + getSize((*node)->rchild) + 1;
	*node = temp;
}

void right_rotate(SBTreeNode **node)
{
	SBTreeNode *temp = (*node)->lchild;
	(*node)->lchild = temp->rchild;
	temp->rchild = *node;
	temp->size = getSize(*node);
	(*node)->size = getSize((*node)->lchild) + getSize((*node)->rchild) + 1;
	*node = temp;
}
